Abstract Inactivity is a common problem among older kidney transplant recipients (KTRs) and is associated with their high incidence of obesity and cardiovascular problems which are the leading cause of death for KTRs. However, the combination of SystemCHANGETM + activity trackers holds promise for increasing activity. The short-term goals of this Mentored Patient-Oriented Research Career Development Award (K23) are to implement these interventions and obtain preliminary data on older adult KTRs. Sixty KTRs age 65 and older will be recruited from a Mid-South transplant center to determine: (I) if perceptions (usability, sustainability, and acceptability) of activity tracker use differ for older adult KTRs participating in a SystemCHANGETM intervention compared to a control group at 1, 2, 3, 6, & 12 months and (II) the degree to which a SystemCHANGE? + activity tracker intervention improves physical activity (steps per day), functional ability, health outcomes (blood pressure, heart rate, waist circumference, and body mass index) and quality of life for older adult KTRs from baseline to 3, 6, & 12 months compared to a control group using only activity trackers . The long-term goal is to develop the candidate as an independent investigator prepared to lead randomized clinical trials focused on maximizing physical activity among older chronically ill adults. The proposed training is in line with NINR- supported initiatives and represents a logical progression from the candidate's prior research training. Career development objectives are to: (1)gain expertise with the theoretically-based SystemCHANGE? intervention and work with informatics experts, (2) develop a stronger knowledge base for the responsible conduct of scientific research and the field of kidney transplantation, (3)develop proficiency in the use of statistical techniques for the analysis of continuously monitored data (i.e., daily steps taken), (4)develop skills in the conduct of randomized clinical trials (RCT) at the core of the proposed study, (5)actively engage in the ongoing RCT study of mentors called the Medication Adherence Given Individual Change (MAGIC) and observe the case manager at the transplant clinic, (6) implement the proposed K23 research project, and (7)analyze and use preliminary data from the K23 pilot study to prepare an ?R01?grant to test the efficacy of personalized mobile health interventions for physical activity in a multi-site RCT. Career objectives will be accomplished through didactic courses; participation in national conferences and institutes; and hands-on research training under the mentorship of an accomplished team of scientists in the field of kidney transplantation (Hathaway and Russell), SystemCHANGETM (Moore and Russell), physical activity in older adults (Resnick), mobile activity trackers and the integration of large monitoring data sets (Ertin), clinical trials (Russell), and quantitative methods (Hathaway). The skills, experience, and data gained from this career development award will position the candidate to advance behavioral self-management interventions focused on maximizing physical activity for older chronically ill adults.